package com.yuanss.smart.framework.helper;

import com.yuanss.smart.framework.util.CollectionUtil;
import com.yuanss.smart.framework.util.PropsUtil;
import org.apache.commons.dbcp2.BasicDataSource;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;
import org.apache.commons.dbutils.handlers.MapListHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Properties;

/**
 * @Description 数据库操作助手类
 * @Date 2024/11/14 下午3:56
 * @Created by 菜到不敢run
 */
public final class DatabaseHelper {
    private static final Logger LOGGER = LoggerFactory.getLogger(DatabaseHelper.class);

    private static final String DRIVER;
    private static final String URL;
    private static final String USERNAME;
    private static final String PASSWORD;

    // DBUtil
    private static final QueryRunner QUERY_RUNNER = new QueryRunner();

    // 隔离线程
    private static final ThreadLocal<Connection> CONNECTION_HOLDER = new ThreadLocal<Connection>();

    // DBCP数据库连接池
    private static final BasicDataSource DATA_SOURCE = new BasicDataSource();

    static {
        Properties conf = PropsUtil.loadProps("smart.properties");
        DRIVER = conf.getProperty("smart.framework.jdbc.driver");
        URL = conf.getProperty("smart.framework.jdbc.url");
        USERNAME = conf.getProperty("smart.framework.jdbc.username");
        PASSWORD = conf.getProperty("smart.framework.jdbc.password");

        DATA_SOURCE.setDriverClassName(DRIVER);
        DATA_SOURCE.setUrl(URL);
        DATA_SOURCE.setUsername(USERNAME);
        DATA_SOURCE.setPassword(PASSWORD);
    }

    /**
     * 获取数据库连接
     */
    public static Connection getConnection(){
        Connection conn = CONNECTION_HOLDER.get();
        if (conn == null){
            try {
                conn = DATA_SOURCE.getConnection();
            } catch (SQLException e) {
                LOGGER.error("get connection failure", e);
                throw new RuntimeException(e);
            } finally {
                CONNECTION_HOLDER.set(conn);
            }
        }
        return conn;
    }


    /**
     * 查询实体列表
     */
    public static <T> List<T> queryEntityList(Class<T> entityClass, String sql, Object... params){
        List<T> entityList;
        try {
            Connection conn = getConnection();
            entityList = QUERY_RUNNER.query(conn, sql, new BeanListHandler<T>(entityClass), params);
        } catch (SQLException e) {
            LOGGER.error("query entity list failure", e);
            throw new RuntimeException(e);
        }
        return entityList;
    }

    /**
     * 查询实体
     */
    public static <T> T queryEntity(Class<T> entityClass, String sql, Object... params){
        T entity;
        try {
            Connection conn = getConnection();
            entity = QUERY_RUNNER.query(conn, sql, new BeanHandler<T>(entityClass), params);
        } catch (SQLException e){
            LOGGER.error("query entity failure", e);
            throw new RuntimeException(e);
        }
        return entity;
    }

    /**
     * 可进行联表查询，返回一个List<Map>
     */
    public static List<Map<String, Object>> executeQuery(String sql, Object... params){
        List<Map<String, Object>> result;
        try {
            Connection conn = getConnection();
            result = QUERY_RUNNER.query(conn, sql, new MapListHandler(), params);
        } catch (Exception e){
            LOGGER.error("execute query failure", e);
            throw new RuntimeException(e);
        }
        return result;
    }

    /**
     * 执行更新语句 (包括update/insert/delete), 返回更新的行数
     */
    public static int excuteUpdate(String sql, Object... params){
        int rows = 0;
        try {
            Connection conn = getConnection();
            rows = QUERY_RUNNER.update(conn, sql, params);
        } catch (SQLException e){
            LOGGER.error("execute update failure", e);
            throw new RuntimeException(e);
        }
        return rows;
    }

    /**
     * 插入实体
     */
    public static <T> boolean insertEntity(Class<T> entityClass, Map<String, Object> fieldMap){
        if (CollectionUtil.isEmpty(fieldMap)){
            LOGGER.error("can not insert entity");
            return false;
        }
        String sql = "INSERT INTO " + getTableName(entityClass);
        StringBuilder columns = new StringBuilder("(");
        StringBuilder values = new StringBuilder("(");
        for (String fieldName : fieldMap.keySet()){
            columns.append(fieldName).append(", ");
            values.append("?, ");
        }
        columns.replace(columns.lastIndexOf(", "), columns.length(), ")");
        values.replace(values.lastIndexOf(", "), values.length(), ")");
        sql += columns + " VALUES " + values;
        Object[] params = fieldMap.values().toArray();
        return excuteUpdate(sql, params) == 1;
    }

    /**
     * 更新实体
     */
    public static <T> boolean updateEntity(Class<T> entityClass, long id, Map<String, Object> fieldMap){
        if (CollectionUtil.isEmpty(fieldMap)){
            LOGGER.error("can not update entity: fieldMap is empty");
            return false;
        }
        String sql = "UPDATE " + getTableName(entityClass) + " SET ";
        StringBuilder columns = new StringBuilder();
        for (String fieldName : fieldMap.keySet()){
            columns.append(fieldName).append("=? ");
        }
        sql += columns.substring(0, columns.lastIndexOf(", ")) + " WHERE id=?";
        List<Object> paramList = new ArrayList<Object>();
        paramList.addAll(fieldMap.values());
        paramList.add(id);
        Object[] params = paramList.toArray();
        return excuteUpdate(sql, params) == 1;
    }

    /**
     * 删除实体
     */
    public static <T> boolean deleteEntity(Class<T> entityClass, long id){
        String sql = "DELETE FROM " + getTableName(entityClass) + " WHERE id=?";
        return excuteUpdate(sql, id) == 1;
    }

    /**
     * 执行SQL文件
     */
    public static void executeSqlFile(String filePath){
        InputStream is = Thread.currentThread().getContextClassLoader().getResourceAsStream(filePath);
        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
        try {
            String sql;
            while ((sql=reader.readLine()) != null){
                excuteUpdate(sql);
            }
        } catch (Exception e){
            LOGGER.error("execute sql file failure", e);
            throw new RuntimeException(e);
        }
    }

    /**
     * 获取数据库表名
     */
    private static String getTableName(Class<?> entityClass){
        return entityClass.getSimpleName();
    }

    /**
     * 开启事务
     */
    public static void beginTransaction(){
        Connection conn = getConnection();
        if (conn != null){
            try {
                conn.setAutoCommit(false);
            } catch (SQLException e) {
                LOGGER.error("begin transaction failure", e);
                throw new RuntimeException(e);
            } finally {
                CONNECTION_HOLDER.set(conn);
            }
        }
    }

    /**
     * 提交事务
     */
    public static void commitTransaction(){
        Connection conn = getConnection();
        if (conn != null){
            try {
                conn.commit();
                conn.close();
            } catch (SQLException e) {
                LOGGER.error("commit transaction failure", e);
                throw new RuntimeException(e);
            } finally {
                CONNECTION_HOLDER.remove();
            }
        }
    }

    /**
     * 回滚事务
     */
    public static void rollbackTransaction(){
        Connection conn = getConnection();
        if (conn != null){
            try {
                conn.rollback();
                conn.close();
            } catch (SQLException e) {
                LOGGER.error("rollback transaction failure", e);
                throw new RuntimeException(e);
            } finally {
                CONNECTION_HOLDER.remove();
            }
        }
    }
}
